This invention relates to devices for anchoring a trocar sleeve to a patient's body. More particularly, this invention relates to such devices by which the longitudinal position of the sleeve with respect to the patient's body can be easily adjusted.
Trocars are surgical instruments having an obturator with a sharp pointed stylet for piercing a body wall and a tubular sleeve which surrounds the obturator. A trocar assembly thus formed is manually forced by a surgeon with the sharp stylet of the obturator serving to pierce the body wall so as to provide an opening for the tubular sleeve. After the trocar sleeve is in communication with a body cavity, the obturator is removed such that an endoscopic instrument may be inserted into the cavity through the sleeve for performing endoscopic surgery within the cavity.
The trocar sleeve, in order to thus serve as a passageway for various surgical instruments, must remain securely anchored to the patient's body so as not to be easily pulled out of its inserted position. A currently available prior art device for serving this purpose may be characterized as being of a double-gasket structure with an inner tubular member mounted to the sleeve and an outer tubular plug engaging with the inner tubular member and having a helical thread on its outer surface. With a prior art device thus structured, the longitudinal position of the sleeve is not easily adjustable with respect to the patient's body.